The King Neptune’s Tonic is a modern cocktail that was created by Karen Fu in New York City, New York. The recipe features an eclectic mix of flavors that you don’t usually see in a tonic drink, including nutty Oloroso sherry and aged rum as the base, coffee liqueur, and quinine from the tonic water as an accenting bitter note rather than in a prominent role.
Add sherry, rum, and coffee liqueur to a mixing glass.
Fill mixing glass with cubed ice.
Using a bar spoon, stir for 30-45 seconds until well-chilled and slightly diluted.
Fill a highball glass with fresh cracked ice.
Using a julep strainer, strain into highball glass.
Top with tonic water.
Using a bar spoon, stir for 3-5 seconds.
Garnish with lemon twist.